Dr. Elysa Marco is a cognitive-behavioral child neurologist with expertise in the genetics of mental retardation and autism. She is supported by the academic excellence of the University of California, San Francisco's Neurology, Psychiatry, Radiology, and Neuroscience departments. Her long term research objectives are to use magetic source imaging (MSI) to: (1) probe the etiology of autism, (2) facilitate early accurate diagnosis, and (3) create an objective measure of cognitive processing for use in treatment trials. The goal of this study is to ascertain whether individuals with autism show local cortical hyper-excitation that directly correlates with behaviorally observed sensory over-reactivity. The rationale is that individuals with autism have high rates of sensory processing difficulties and previous studies have documented abnormalities in cortical structure and connectivity. The specific aims are to (1) use traditional and advanced MSI techniques to assess early tactile and auditory processing in the primary sensory cortex;and (2) correlate these findings with detailed measures of tactile and auditory sensitivity. MSI spatial adaptive filtering algorithms allows for precise assessment of brain activity in time, space, and in oscillatory frequency. This technique represents a novel and promising extension of previous work in the field. This cross-sectional case-control study will assess sensory processing in boys (9-11 years) with autism and a performance IQ >70 relative to matched healthy controls. Diagnostic evaluation, cognitive testing, objective sensory assessment, MEG, and MRI will be conducted on 20 children with autism and 20 healthy controls. In addition, to contributing to the understanding of sensory processing in autism, this project will support Dr. Marco's training in neuroimaging, neuropsychology, cognitive neuroscience, and biostatistic so that she can become in independent patient oriented researcher. PUBLIC HEALTH RELEVANCE: Autism spectrum disorders (ASD) permeate the social, emotional, and economic life of the affected individual and their community. ASD is now estimated to affect 1 in 150 individuals and it's underlying neural mechanism remain unclear. This project aims to use the advanced technique of magnetic source imaging to reliably measure the temporal, spatial, and frequency characteristics of neual activity in children with autism during sensory perception. This project will contribute to the understanding of autism and to the development of diagnostic and treatment studies for the future.